Method for managing a life of a storage medium, storage device, storage system, and storage medium

ABSTRACT

A storage medium life management method, storage device and storage system detect the life of a storage medium ( 1 ). Medium life management information ( 14 ) indicating the read/write state of a medium is recorded on the storage medium ( 1 ). A drive ( 5 ) reads out the medium life management information ( 14 ) from the storage medium ( 1 ) when the storage medium ( 1 ) is loaded, and updates the medium life management information ( 14 ) pursuant to the operation of at least one of the reading and writing of storage medium ( 1 ). Then, the drive ( 5 ) writes medium life management information ( 14 ) to the storage medium ( 1 ) when the storage medium ( 1 ) is unloaded. This medium life management information ( 14 ) is used for determination of the life of a medium in either a drive ( 5 ) or host ( 4 ). Since management information corresponding to an actual read/write state can be obtained, the deterioration of a storage medium can be accurately detected.

TECHNICAL FIELD

[0001] The present invention relates to a method of managing a life of astorage medium for storing data, storage device, storage system andstorage medium, and more particularly to a storage medium lifemanagement method, storage device, storage system and storage medium fordetermining the life of a storage medium pursuant to utilizing aremovable storage medium.

BACKGROUND ART

[0002] Storage media capable of being loaded into and unloaded fromstorage drives are used widely. A memory cartridge is a typical suchstorage medium. The memory cartridge has a structure formed by housing adata-storing storage medium in a cartridge case. Memory cartridges suchas this include magnetic disk cartridges, optical disk cartridges,magneto-optical disk cartridges, and magnetic tape cartridges. A memorycartridge is loaded into a drive, and then the drive head accesses thestorage medium in the memory cartridge to perform read/write operations.After read/write operation, the memory cartridge is ejected from thedrive.

[0003] This storage medium has a life. For a storage medium whose lifehas expired, there is the danger that data will not be able to be read.For this reason, technology for managing the life of a storage mediumhas become necessary.

[0004] As methods for managing the life of this storage medium, thefollowing prior methods have been known.

[0005] (1) A drive writes the utilization start time into a memorycartridge, and manages the life of the memory cartridge by the elapsedtime from the utilization start time.

[0006] (2) A drive writes the number of loads into a memory cartridge,reads out the number of loads, and manages the life of the memorycartridge according to the number of loads.

[0007] However, the problem has been that a method for managing life bythe time that elapses from a utilization start time and a method formanaging life by the number of loads do not necessarily show thedeterioration of the storage medium or the deterioration of the data onthe storage medium. That is, in addition to performance deteriorationresulting from age deterioration of the storage medium itself, the lifeof a storage medium also deteriorates as a result of the storage mediumbeing used. For example, the surface of a magnetic tape is worn bycoming in contact with a magnetic head, causing performance todeteriorate. Also, dust and the like adhere to the surface of the tape,causing performance to deteriorate. Phenomena such as this also occurfor disks and other media besides tape.

[0008] For the prior art, the life of a storage medium was determined tobe over when a specified utilization period elapsed even if only onedata-write operation had been performed. Or, the life of a storagemedium was determined to be over when a specified number of loads hadbeen exceeded even though only a small quantity of data was accessed onthe storage medium at each load. In cases such as these, there waspractically no deterioration of the storage medium. Thus, thereplacement of the storage medium had to be carried out despite the factthat the storage medium had not deteriorated. This was a problem becauseit wastefully increased the costs of storage media for users.

[0009] By contrast, when the utilization frequency of a storage mediumis extremely high, or when there is a large volume of input/output dataat each load, the medium deteriorates prior to a specified value for autilization period or number of loads. Consequently, the problem wasthat loss of user data and other such problems occurred before thespecified value for a utilization period or number of loads.

[0010] Furthermore, the results of a determination of the life of astorage medium were only displayed on the indicator of the storagedevice thereof, and were not communicated to the management system ofthis storage device. An operator had to look at the indicator content ofa storage device to manage the life of a storage medium. Thus, theproblem was that a host or other management system could not manage thelife. For automated storage systems such as a library system inparticular, managing the life of a storage medium was really difficult.

[0011] Therefore, an object of the present invention is to provide astorage medium life management method, storage device, storage system,and storage medium for determining life based on the deterioration ofthe storage medium.

[0012] Further, an object of the present invention is to provide astorage medium life management method, storage device, storage system,and storage medium for preventing the wasteful replacement of a storagemedium and loss of data.

[0013] Furthermore, an object of the present invention is to provide astorage medium life management method, storage device, storage system,and storage medium for collecting management information, whichindicates life based on the deterioration of a storage medium.

[0014] Furthermore, an object of the present invention is to provide astorage medium life management method, storage device, storage system,and storage medium for automatically determining life according to thedeterioration of a storage medium.

[0015] Furthermore, an object of the present invention is to provide astorage medium life management method, storage device, storage system,and storage medium for determining life according to the deteriorationof a storage medium for an automated storage system as well.

DISCLOSURE OF THE INVENTION

[0016] The present invention is a storage device for accessing a loadedstorage medium, and reading and writing data to and from theabove-mentioned storage medium. And the method for managing the life ofthis storage medium comprises the steps of reading medium lifemanagement information from the above-mentioned loaded storage medium;detecting an operating condition of at least one of the reading and thewriting of data in the above-mentioned storage medium, and updating theabove-mentioned medium life management information in accordance withresults of such detection; and writing the above-mentioned updatedmedium life management information to the above-mentioned storage mediumupon unloading the storage medium.

[0017] In the present invention, based on the experience that the lifeof a storage medium is related to actual read/write operations, theoperating condition of at least one of the reading and the writing of astorage medium is detected, and the detected result is utilized in theinformation for managing the life of a medium. Then, by storing thismedium life management information on the storage medium, reading it outat loading time, updating it, and then rewriting it to the storagemedium, a history of management information is retained on the storagemedium. Because operating conditions, such as operating time, number ofdata errors and number of servo errors at read/write are treated asmanagement information, the deterioration of a storage medium can beaccurately detected. Thus, it is possible to prevent wasteful storagemedium replacement and data loss.

[0018] Another aspect of the present invention further comprises a stepfor reporting the above-mentioned medium life management information toa management device for managing the life of the above-mentioned storagemedium. Thus, a determination of life becomes possible by a managementdevice that is separate from a storage device, making it easy for anoperator to confirm the life of a storage medium.

[0019] Another aspect of the present invention further comprises a stepfor analyzing the above-mentioned medium life management information anddetermining the life of the above-mentioned storage medium. Because thelife of a storage medium is also determined, this determination can bedisplayed on a storage device indicator or a management device, and anoperator can be prompted to replace a storage medium.

[0020] Another aspect of the present invention further comprises a stepfor setting determination parameters for the above-mentioneddetermination step. Since it is possible to change a determinationcondition, a life determination can be executed in accordance with auser request.

[0021] Another aspect of the present invention further comprises a stepfor reporting the above-mentioned determination results to a managementdevice for managing the life of the above-mentioned storage medium.Because the determination results are reported to a management devicethat is separate from the storage device, the management device canmanage the life of a storage medium. For this reason, managing the lifeof a storage medium can be automated by an automatic storage systemusing the management device.

[0022] In another aspect of the present invention, the above-mentionedupdating step comprises steps for detecting a plurality of states of atleast one of the reading and the writing of data in the above-mentionedstorage medium, and for updating the above-mentioned medium lifemanagement information in accordance with each of the above-mentionedplurality of states.

[0023] Since a plurality of states are detected and treated asmanagement information, the deterioration of a storage medium can bedetermined from a variety of perspectives.

[0024] Another aspect of the present invention also has steps foranalyzing each of the plurality of states of the above-mentioned mediumlife management information, and for determining the life of theabove-mentioned storage medium from the results of each analysis.Because a determination is made by combining the results of respectiveanalyses of a plurality of states, a variety of factors can be analyzed,making possible an accurate life determination.

[0025] In another aspect of the present invention, the above-mentioneddetermination step comprises steps for determining the life of theabove-mentioned storage medium based on the above-mentioned respectiveanalyses results, and detecting the reason for the above-mentioneddetermination. Since the reason for a determination is also detected,deterioration factors can be communicated to an operator, and theoperator can make an accurate decision about replacement.

[0026] In another aspect of the present invention, the above-mentionedupdating step comprises steps for detecting an operating quantity of atleast one of the reading and the writing of data when data is read orwritten from/to the above-mentioned storage medium, and for updating theabove-mentioned medium life management information according to resultsof such detection. Since operating quantities such as operating time ornumber of operating paths, constitute medium deterioration factors, adetermination of medium life is made by detecting these factors.

[0027] In another aspect of the present invention, the above-mentionedupdating step comprises steps for detecting data error states of atleast one of the reading and the writing of data when data is read orwritten from/to the above-mentioned storage medium, and for updating theabove-mentioned medium life management information according to thedetection results. Since data error states, such as the number of dataerrors, directly affect the read/write performance of a storage medium,a determination can be made regarding the deterioration of a storagemedium regardless of the elapsed time.

[0028] In another aspect of the present invention, the above-mentionedupdating step comprises steps for detecting head servo error sate of atleast one of the reading and the writing of the above-mentioned storagemedium data, and for updating the above-mentioned medium life managementinformation according to the detection results. When there are frequenterror states of a servo controller for positioning a head on a storagemedium, it is possible to make a determination that the storage mediumon which the servo information is stored has deteriorated, and it is forthis reason that servo error states are used as management information.

[0029] In storage system of the present invention, the storage device isconstituted by a library system having a storage drive that accesses aloaded storage medium, and reads/writes data from/to the above-mentionedstorage medium, and an accessor for loading a desired storage mediuminto the above-mentioned storage drive, and removing the above-mentionedstorage medium from the above-mentioned storage drive. In a librarysystem, in which an accessor performs the handling of a storage medium,because a storage medium is moved around in a closed space inside thedevice, it is difficult for an operator to see a storage medium and makea determination as to its life. Thus, the storage system of the presentinvention is constituted such that, by reporting medium life managementinformation to a management device of the library system, the life of astorage medium inside the library system is managed by the managementdevice. For this reason, the life of a storage medium can be easilymanaged even in an automated storage system just like in the librarysystem, making it possible to incorporate the present invention in anautomated system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030]FIG. 1 is a block diagram of a magnetic tape drive of anembodiment of the present invention;

[0031]FIG. 2 is a schematic of a magnetic tape storage system of anembodiment of the present invention;

[0032]FIG. 3 is the recording format of the magnetic tape of themagnetic tape cartridge of FIG. 2;

[0033]FIG. 4 and FIG. 5 are charts describing medium managementinformation of an embodiment of the present invention;

[0034]FIG. 6 is a load process flow chart for the constitution of FIG.1;

[0035]FIG. 7 is an unload process flow chart for the constitution ofFIG. 1;

[0036]FIG. 8 is a write process flow chart for the constitution of FIG.1;

[0037]FIG. 9 is a read/read reverse process flow chart for theconstitution of FIG. 1;

[0038]FIG. 10 is a sense command process flow chart for the constitutionof FIG. 1;

[0039]FIG. 11 is a read buffer command process flow chart for theconstitution of FIG. 1;

[0040]FIG. 12 is a chart describing threshold reach check items for theconstitution of FIG. 1;

[0041]FIG. 13 is a chart describing threshold reach codes for theconstitution of FIG. 1;

[0042]FIG. 14 is a life determination process flow chart (Part 1) forthe constitution of FIG. 1;

[0043]FIG. 15 is a life determination process flow chart (Part 2) forthe constitution of FIG. 1;

[0044]FIG. 16 is a chart describing the medium replacement display ofthe constitution of FIG. 1;

[0045]FIG. 17 is a schematic of a library system of another embodimentof the present invention;

[0046]FIG. 18 is a block diagram of the constitution of FIG. 17; and

[0047]FIG. 19 is a chart describing the medium replacement display ofthe constitution of FIG. 17.

BEST MODE FOR CARRYING OUT THE INVENTION

[0048] A life management method, storage device and storage system ofthe present invention will be explained using a magnetic tape cartridgestorage device as an example.

Magnetic Tape Cartridge Storage Device

[0049]FIG. 1 is a block diagram of a magnetic tape cartridge storagedrive of an embodiment of the present invention, FIG. 2 is a schematicof a magnetic tape storage system of an embodiment of the presentinvention, FIG. 3 is the recording format of the magnetic tape of themagnetic tape cartridge of FIG. 2, and FIG. 4 and FIG. 5 are chartsdescribing medium management information of an embodiment of the presentinvention.

[0050] As shown in the system schematic of FIG. 2, a magnetic tapecartridge storage drive (hereinafter referred to as an MT drive) 5 isconnected to a host 4, and, in accordance with commands from host 4,performs read/write for a magnetic tape cartridge (hereinafter referredto as a medium) 1. The host 4 constitutes, for example, a personalcomputer or the like. The medium 1 is constituted by housing a magnetictape inside a cartridge case, and can be loaded and unloaded into andfrom MT drive 5.

[0051] As shown in FIG. 1, the MT drive 5 is constituted from a magnetictape drive unit (hereinafter referred to as an MTU) 2, and a magnetictape controller (referred to as an MTC) 3. MTC 3 controls MTU 2 inaccordance with commands from the host, and performs read/write formedium 1. MTU 2 has a magnetic head, a tape unit for loading, runningand unloading the magnetic tape of medium 1, a head positioning unit forpositioning the magnetic head on the desired track of the magnetic tape,and a process for controlling these.

[0052] MTC 3 has a microprocessor (called an MPU) 30 for overallcontrol, CS memory 31, which stores control information, a SCSI (smallcomputer system interface) interface circuit (called an SCSI I/F) 35 forthe SCSI interface with host 4, a buffer memory 36, and a read/writecontrol circuit (R/W circuit) 37.

[0053] CS memory 31 has a region 34 for storing firmware codes, a region33 for storing control information, and a Table 32 for storinginformation for managing the life of a medium, which will be describedbelow. MPU 30 processes commands from host 4 in accordance with thefirmware codes and control information on CS memory 31. The flow ofinformation between the medium 1 and the host 4 is host 4 —SCSI I/F 35—buffer memory 36 —R/W circuit 37 —medium 1.

[0054] The MTU 2 processor detects servo errors. Further, MTU 2 iscontrolled by MPU 30, runs medium 1, and positions the magnetic head.R/W circuit 37 sends buffer memory 36 information to the magnetic head,and performs write operations. Further, R/W circuit 37 carries out readcontrol, which transmits data read out by the magnetic head to buffermemory 36 in accordance with the commands of MPU 30. R/W circuit 37comprises a well-known data error detecting circuit and an ECC (errorcorrecting code) correction circuit.

[0055] As shown in FIG. 3, the format of the magnetic tape has, from theBOT (beginning of tape), an SAQ region (Servo Acquisition Region) 10, aVCR region (Volume Control Region) 11, and a DR region (Data Region) 12.SAQ region 10 is the region used for magnetic head servo tracking, anddata is not written to this region. The magnetic head is positioned on atrack of the magnetic tape based on the servo data of this SAQ region10. VCR region 11 is the recording region in which medium managementinformation is recorded. The medium life management information 14 ofthe present invention is recorded in this region 11.

[0056] DR region 12 is a user data recording region. DR region 12 isdivided vertically into eight regions (paths). These regions are calledHalfwraps. The magnetic head accesses the entire DR region by moving inthe direction of the arrows shown in FIG. 3 from Halfwrap 0 to Halfwrap7. For example, each Halfwrap constitutes 16 data channels and threeservo channels.

[0057]FIG. 4 and FIG. 5 are charts describing relevant medium lifemanagement information.

[0058] The medium life management information 14 constitutes generallife management information, servo error information, and data errorinformation. The general life management information comprises thedistance and number of processing bytes read/written on a tape. In otherwords, it is tape travel time, which is the time that the tape isactually operated during read/write, number of tape travel paths, whichis the number of paths that a tape is made to travel during read/write,total number of processing bytes (write), which is the number of bytesread/written to a tape during write operations, and total number ofprocessing bytes (read), which is the number of bytes read/written froma tape during read operations. All of these indicate read/writeoperation quantities, and are effective for evaluating the deteriorationof the tape itself due to use.

[0059] Next, servo error information comprises the frequency and historyof servo errors that occur while reading/writing from/to a medium. Thatis, it is SDM (Servo Demark Mark) write frequency, number of servoretries, number of initial head retries, the tracking error ratehistory, and the average value of the tracking error rate.

[0060] As explained hereinabove, the magnetic head is positioned andcontrolled on a data track by servo information of a magnetic tape servotrack. The number of servo retries is the number of times that themagnetic head goes off track from a servo track during a writeoperation. Further, because SDM indicates a region in which servotracking cannot be performed, SDM is mark data that is written so as toinsert the data track of this region. The start position is called SDMbegin, and the end position is called SDM END. SDM write frequencyindicates the number of times that the above-mentioned mark is writtenduring write operations.

[0061] The magnetic head is positioned in a track direction by servoinformation of SAQ region 10 of the tape. The number of initial headretries indicates the number of times that initial head retry wasperformed while positioning the servo according to this SAQ region 10.The tracking error rate is arrived at by dividing the number of bytes(Kbytes) written by the number of SDM write-in (per load). As shown inFIG. 4, tracking error rate information constitutes a history oftracking error rates from the most recent to the one 16 timestherebefore. The average value of a tracking error rate is obtained bydividing the above-mentioned prior number of tracking error rates by thenumber of times the medium has been loaded.

[0062] The servo error information thereof enables the deterioration ofa medium to be evaluated from the standpoint of performance. That is,the deterioration of tape performance can be detected via servoinformation written to the tape.

[0063] Next, data error information is the number of blocks/number ofbytes/number of retries when processing a medium during a single loadoperation. Data error information comprises the following respectiveinformation.

[0064] It is the number of read processing bytes and the number of writeprocessing bytes per load during read/write. The number of readprocessing bytes represents the total number of bytes during a readoperation. The number of write processing bytes represents the totalnumber of bytes during a write operation. As shown in FIG. 4, theseconstitute a history of number of read/write processing bytes from themost recent to that 16 times therebefore.

[0065] Moving to FIG. 5, the number of write blocks is the number ofdevice blocks actually written to a medium. The number of read blocks isthe number of device blocks actually read from a medium. The totalnumber of write retries is the number of retries that occurred whenwriting to a medium. The total number of read retries is the number ofretries that occurred when reading from a medium. The total number ofread reverse retries is the number of retries that occurred whenreverse-reading a medium.

[0066] The total number of write retry blocks is the number of deviceblock retries that occurred when writing to a medium. The total numberof read retry blocks is the number of device block retries that occurredwhen reading from a medium. The total number of read reverse retryblocks is the number of device block retries that occurred whenreverse-reading a medium.

[0067] The number of write ECC corrections is the number of ECCcorrections during write operations, the number of read ECC correctionsis the number of ECC corrections during read operations, and the numberof read reverse ECC corrections is the number of ECC corrections duringread reverse operations. Read data error rate information indicates thefrequency of occurrence of data errors relative to the number of bytesread. Write data error rate information indicates the frequency ofoccurrence of data errors relative to the number of bytes written. Readreverse data error rate information indicates the frequency ofoccurrence of data errors relative to the number of read-reverse bytes.As shown in FIG. 5, these data error rates are accumulated in historiesfrom the most recent to the one 16 times therebefore.

[0068] As shown in FIG. 4, the average value of a write data error rateis the average value relative to the number of loads for the write dataerror rate. The average value of a read/read reverse data error rate isthe average value relative to the number of loads for the read/readreverse data error rate.

[0069] Data error information like this enables the deterioration of amedium to be evaluated from the standpoint of performance. That is, thedeterioration of tape performance can be detected by the datainformation written to the tape.

[0070] Furthermore, a medium life-indicating threshold reach code, whichwill be described below, is also stored as medium life managementinformation (Refer to FIG. 4).

[0071] Not all such-general management information, servo errorinformation, and data error information needs to be stored. Rather, thisinformation can be selected as needed in accordance with determinationparameters for a life determination, and life analysis conditions.

Magnetic Tape Read/Write Operations

[0072]FIG. 6 is a load process flow chart of when a medium is loaded.FIG. 7 is an unload process flow chart of when a medium is unloaded,FIG. 8 is a write process flow chart, and FIG. 9 is a read/read reverseprocess flow chart.

[0073] A loading operation will be explained using FIG. 6.

[0074] (S1) Insertion of the medium 1 into MT drive 5 is detected.

[0075] (S2) MTU 2 performs a mechanical loading operation. That is, themagnetic tape is pulled out from medium 1, and wrapped around the drivereel.

[0076] (S3) Magnetic head is tracked using SAQ region 10 of medium 1.

[0077] (S4) After tracking, the magnetic head reads out the VCR region11 of the magnetic tape to the buffer memory 36. Then, in accordancewith commands from MPU 30, the VCR region 11, which was read to thebuffer memory 36, is developed to CS memory 31. In accordance therewith,the medium life management information 14 of VCR region 11 is developedto the Table 32 of CS memory 31.

[0078] (S5) Then, MPU 30 positions the magnetic head of MTU 2 to the DRregion of the magnetic tape, and terminates the load process. In thisstate, the MT drive 5 is waiting for a read/write command from the host.

[0079] An unloading operation will be explained using FIG. 7.

[0080] (S6) Magnetic tape is rewound upon receipt of an unload command.

[0081] (S7) MPU 30 creates VCR region 11 data, comprising updated mediumlife management information (This will be explained in the read/writeprocess described hereinbelow) of Table 32 in CS memory 31.

[0082] (S8) Then, the created data is written to VCR region 11 of themagnetic tape. In accordance therewith, the medium life managementinformation 14 of VCR region 11 on the magnetic tape is overwritten withthe updated medium life management information.

[0083] (S9) Then, MTU 2 executes a mechanical unloading operation, andthereafter, the medium 1 is ejected, and unloading is terminated.

[0084] Next, updating operations for medium life management informationat write/read/read reverse will be explained. First, the write processwill be explained in line with FIG. 8.

[0085] (S10) A write command from host 4 is communicated to MPU 30 viaSCSI I/F 35, and write data from host 4 is buffered in buffer memory 36by way of SCSI I/F 35.

[0086] (S11) MPU 30 gives instructions for tape write to MTU 2 and R/Wcircuit 37. R/W circuit 37 reads out data from the buffer memory 36 inone block units, and writes to the tape via the magnetic head of MTU 2.

[0087] (S12) MTU 2 detects servo errors, and R/W circuit 37 detects dataerrors. MPU 30 detects the error state thereof and controls retry. MPU30 determines whether or not there is an error (data error, servoerror).

[0088] (S13) When there is an error, MPU 30 determines whether or notthe error is an off-track error. When it is an off-track error, MPU 30updates the servo error information of Table 32 by adding “138 to thenumber of servo retries (FIG. 4).

[0089] (S14) MPU 30 counts the number of MTU 2 retries, and determineswhether or not the number of retries exceeds a specified value. If thenumber of retries exceeds a specified value, MPU 30 executes an errorend. Conversely, if the number of retries does not exceed a specifiedvalue, MPU 30 updates the data error information of Table 32 by addingthe number of write retries (FIG. 5). Then, processing returns to StepS11.

[0090] (S15) MPU 30 determines whether or not R/W circuit 37 wrote anSDM. When an SDM has been written, MPU 30 updates the servo errorinformation of Table 32 by adding the number of SDM writes (FIG. 4).

[0091] (S16) MPU 30 updates the data error information of Table 32 byadding the number of blocks written (FIG. 5). Then, MPU 30 updates thegeneral management information of Table 32 by adding the total number ofbytes written. Furthermore, MPU 30 adds the number of bytes written tothe per-load number of bytes of data error information in Table 32.

[0092] (S17) MPU 30 determines whether or not there was a retry by MTU2. If there was a retry, it updates the data error information of Table32 by adding the number of write retries (FIG. 5). Further, MPU 30updates data error information of Table 32 by adding the number of ECCcorrections (FIG. 5).

[0093] (S18) MPU 30 determines whether or not the writing of all of thewrite data from host 4 has ended. When it has not ended, processingreturns to Step S11.

[0094] (S19) By contrast, when writing has ended, MPU 30 instructs MTU 2to stop the tape. Then, MPU 30 obtains tape travel time from MTU 2management information, and updates the general management informationof Table 32 by adding the tape travel time (FIG. 4). Furthermore, MPU 2obtains the number of tape travel paths, and updates the generalmanagement information of Table 32 by adding the number of paths thetape traveled (FIG. 4).

[0095] Furthermore, MPU 30 computes the write error rate from the numberof bytes written and the above-mentioned number of retries, and updatesthe history of write error rate information in Table 32. Then, MPU 30calculates the error rate average value from the updated history ofwrite error rate information. Similarly, MPU 30 updates the trackingerror rate information of Table 32, and updates the average value of thetracking error rate. Then, it executes a normal end.

[0096] Thus, general management information (tape travel time, number oftape travel paths, total number of bytes written) is updated pursuant toa write operation. Further, servo error information (SDM writeinformation, number of servo retries, tracking error rate, average valueof tracking error rate) is updated. Similarly, data error information(number of blocks written, number of write retries, number of byteswritten per load, number of ECC corrections, write data error rate, andaverage write data error rate) is updated.

[0097] Next, read/read reverse processing will be explained using FIG.9.

[0098] (S20) A read command from host 4 is communicated to MPU 30 viaSCSI I/F 35. MPU 30 instructs MTU 2 and R/W circuit 37 to execute taperead. In accordance therewith, a data read operation is performed oneblock at a time. The read data is transmitted to host 4 via buffermemory 36 and SCSI I/F 35.

[0099] (S21) MTU 2 detects servo errors, and R/W circuit 37 detects dataerrors. MPU 30 reads the error state thereof, and determines whether ornot there is an error (data error, servo error).

[0100] (S22) When there is an error, MPU 30 determines whether or notthe number of MTU 2 read retries exceeds a specified value. If thenumber of retries exceeds a specified value, error end is executed. Bycontrast, when the number of retries does not exceed a specified value,MPU 30 updates the data error information of Table 32 by adding thenumber of read/read reverse retries (FIG. 5). Then, processing returnsto Step S20.

[0101] (S23) When there is no error, MPU 30 updates the data errorinformation of Table 32 by adding the number of blocks read in (FIG. 5).Then, MPU 30 updates the general management information of Table 32 byadding the number of bytes read in (FIG. 4). Furthermore, MPU 30 addsthe number of bytes read in to the per-load number of bytes (FIG. 4) ofdata error information in Table 32.

[0102] (S24) MPU 30 determines whether or not there was a retry by MTU 2in a pertinent block. If there was a retry, MPU 30 updates the dataerror information in Table 32 by adding the number of read/read reverseretries (FIG. 5). Further, MPU 30 updates the data error information ofTable 32 by adding the number of ECC corrections (FIG. 5).

[0103] (S25) MPU 30 determines whether or not the reading in of datarequested from host 4 has ended. When it has not ended, processingreturns to Step S20.

[0104] (S26) Conversely, when data read has ended, MPU 30 instructs MTU2 to stop the tape. Then, MPU 30 obtains the tape travel time from MTU 2management information, and updates the general management informationof Table 32 by adding tape travel time (FIG. 4). Furthermore, MPU 30obtains the number of tape travel paths, and updates the generalmanagement information of Table 32 by adding the number of paths thetape traveled (FIG. 4).

[0105] Furthermore, MPU 30 computes the read/read reverse error ratefrom the number of bytes read and the above-mentioned number of retries,and updates the history of read/read reverse error rate information inTable 32. Then, MPU 30 calculates the average value of the read/readreverse error rate from the updated history of read/read reverse errorrate information, and updates the average value of the read/read reverseerror rate of Table 32.

[0106] Thus, general management information (tape travel time, number oftape travel paths, total number of bytes read) is updated pursuant to aread/read reverse operation. Further, data error information (number ofread/read reverse blocks, number of read/read reverse retries, number ofbytes read per load, number of ECC corrections, read/read reverse dataerror rate, and average read/read reverse data error rate) is updated.

[0107] Thus, the updated medium life management information 14 iscommunicated to host 4. Further, medium life management information isanalyzed in MT drive 5, and a life determination code (called athreshold reach code) is communicated to host 4.

[0108] This operation will be explained using the LOG sense processingflow chart of FIG. 10.

[0109] (S30) Normally, when a read/write of MT drive 5 ends, host 4sends a LOG sense command to MT drive 5 to collect MT drive 5 LOGinformation. MPU 30 of MT drive 5 receives this LOG sense command, andexecutes analysis processing (called threshold processing) of the mediumlife management information 14 of Table 32 in CS memory 31. Thisanalysis processing will be explained using FIG. 12 and so forth, whichwill be explained hereinbelow.

[0110] (S31) MPU 30 transmits to host 4 the analysis results (reachcode) obtained via analysis processing. In accordance therewith, host 4is able to detect the life of medium 1.

[0111]FIG. 11 is a flow chart for read buffer processing.

[0112] (S35) Host 4 has a read buffer command as a command for reading aMT drive 5 buffer. In response to this read buffer command, a bufferregion specified by the command buffer ID is transmitted to host 4. Thisbuffer ID specifies the above-mentioned medium life managementinformation (Table) 32.

[0113] When MPU 30 receives a buffer read command, which uses a bufferID to specify Table 32, Table 32 is read out of CS memory 31, and storedin buffer memory 36.

[0114] (S36) The medium life management information 14 of this buffermemory 36 is communicated to host 4.

[0115] Thus, host 4 is able to directly acquire the medium lifemanagement information of medium 1. This is effective when host 4 wishesto obtain the above-mentioned analysis results and learn the causesthereof. Further, it is also possible to construct a system, which doesnot perform the analysis of FIG. 10 in MT drive 5. In this case, host 4is able to make a determination concerning medium life by acquiringmedium life management information via the process in FIG. 11, andanalyzing the acquired medium life management information using a user'sown determination criteria or the analysis process describedhereinbelow.

Analysis of Medium Life Management Information

[0116] MT drive 5 performs the above-mentioned analysis of medium lifemanagement information. That is, when a specified piece of informationof accumulated medium life management information 14 exceeds a thresholdvalue, MT drive 5 reports to host 4 the fact that the medium has reachedthe end of its life (threshold reach).

[0117]FIG. 12 is a chart describing check items for analysis processing,and FIG. 13 is a chart describing threshold reach.

[0118] As shown in FIG. 12, there are a plurality of items to bechecked, and in the histories of the number of tape travel paths, theaverage value of the write data error rate, the average value of thetracking rate, the minimum number of processing bytes, and number ofwrite processing bytes, the number of these items must exceed theminimum number of processing bytes.

[0119] Furthermore, as shown in FIG. 12, as analysis modes for thresholdreach, there are provided a performance-oriented mode, which stresses adrop in performance in the storage device due to an increase in retriesaccompanying the deterioration of a medium, and a medium-oriented mode,which stresses the use of a medium over a long period. And the itemschecked differ for the performance-oriented mode and the medium-orientedmode. In the performance-oriented mode, the number of paths traveled bya tape, which is an index of change due to usage, is removed from thecheck items. The setting of this mode is done either via the operatorpanel of MT drive 5 or by the host.

[0120] Threshold reach is codified so as to make it possible to readilydetermine which information has exceeded the threshold value whenthreshold reach is detected. FIG. 13 is a chart describing thresholdreach codes.

[0121] Code “0×00” indicates that it is not necessary to performthreshold reach. That is, it indicates that more than a specified numberof bytes was processed at each load, but the scope of this overage wasnot a problem.

[0122] Code “0×01” indicates that it is not necessary to performthreshold reach. That is, because processing of more than a specifiednumber of bytes was not carried out at each load, a check of thresholdreach was not performed.

[0123] Code “0×12” indicates that the average write data error rateexceeded a specified number in the performance-oriented mode. Code“0×13” indicates that the average write data error rate exceeds aspecified value, and the number of tape travel paths also exceeds aspecified value. Code “0×14” indicates that within the history of thepast several write data error rates, the average write data error rateexceeded a specified value more than a specified number of times.

[0124] Code “0×22” indicates that the average tracking error rateexceeds a specified value in the performance-oriented mode. Code “0×23”indicates that the average tracking error rate exceeded a specifiedvalue, and the number of tape travel paths also exceeded a specifiedvalue. Code “0×24” indicates that, within the history of the pastseveral tracking error rates, the average tracking error rate exceeded aspecified value more than a specified number of times.

[0125] Code “0×32” indicates the average read/read reverse data errorrate exceeded a specified value in the performance-oriented mode. Code“0×33” indicates that the average read/read reverse data error rateexceeded a specified value, and the number of tape travel paths alsoexceeded a specified value. Code “0×34” indicates that, within thehistory of the past several read/read reverse error rates, the averageread/read reverse error rate exceeded a specified value more than aspecified number of times.

[0126] Threshold reach determination processing will be explained usingFIG. 14 and FIG. 15. FIG. 14 is a determination processing flow chartfor threshold reach relative to a data write.

[0127] (S40) MPU 30 determines whether or not processing in excess of aspecified number of bytes was performed during this load. Whenprocessing in excess of a specified number of bytes has not beenperformed, because a portion of medium 1 is not being accessed, theabove-mentioned updating of medium life management information 14 onlyreflects the portion of medium 1 being accessed. Thus, sincedeterioration cannot be accurately determined even if a check isperformed, threshold reach code “0×01” is set and the operation isterminated.

[0128] (S41) MPU 30 checks the history of the number of write processingbytes, and determines whether or not the number of times, which thenumber of write processing bytes exceeds a specified number of bytes,exceeds a specified number of times. If the number of times, which thenumber of write processing bytes exceeds a specified number of bytes, isless than a specified number of times, as described hereinabove, theabove-mentioned history of medium life management information 14 onlyreflects the portion of medium 1 that is being accessed. Thus, sincedeterioration cannot be accurately determined even if a check isperformed, threshold reach code “0×00” is set without doing a check, andthe operation is terminated.

[0129] (S42) MPU 30 determines whether or not the average value of thehistory of the write data error rate of Table 32 exceeded a specifiedvalue. If it does not exceed a specified value, processing progresses toStep S45. When the average value of the history of the write data errorrate exceeds a specified value, the reporting mode determines whether ornot it is a performance-oriented mode or a medium-oriented mode. When itis a performance-oriented mode, a determination is made that storagedevice performance has declined due to increased retries resulting froma decline in magnetic tape write performance, threshold reach code“0×12” is set, and the operation is terminated.

[0130] (S43) In the medium-oriented mode, MPU 30 determines whether ornot the number of tape travel paths of Table 32 has exceeded a specifiednumber. When the number of tape travel paths exceeds a specified number,a determination is made that magnetic tape write characteristics havedeclined, and deterioration due to long-term use has also occurred,threshold reach code “0×13” is set, and the operation is terminated.

[0131] (S44) When a specified value has been exceeded within the historyof write data error rates of Table 32 (from most recent to 16 timestherebefore), MPU 30 determines whether or not this has occurred morethan a specified number of times. When cases in which a specified valuehas been exceeded occur more than a specified number of times, adetermination is made that magnetic tape write characteristics havedeclined, threshold reach code “0×14” is set, and the operation isterminated. In accordance therewith, the data error check is terminatedand processing moves to a servo error check.

[0132] (S45) MPU 30 determines whether or not the average value of thehistory of the tracking error rate of Table 32 exceeded a specifiedvalue. If it does not exceed a specified value, it is determined thatthat there is no servo error abnormality, threshold reach code “0×00” isset, and the operation is terminated. At this time, even if the averagevalue of the history of the write data error rate exceeded a specifiedvalue in Step S42, when the average value of the history of the trackingerror rate does not exceed a specified value, it is treated as noproblem. The reason for this is to prevent making a determination aboutlife when there is an abnormally high value only in a portion of thewrite data error rate, and the average value is raised due to this.

[0133] (S46) When the average value of the history of the tracking errorrate exceeds a specified value, the reporting mode determines whether ornot it is a performance-oriented mode or a medium-oriented mode. When itis a performance-oriented mode, a determination is made that storagedevice performance has declined due to increased retries pursuant to thedeterioration of the servo track recording characteristics of themagnetic tape, threshold reach code “0×22” is set, and the operation isterminated.

[0134] (S47) In the medium-oriented mode, MPU 30 determines whether ornot the number of tape travel paths of Table 32 has exceeded a specifiednumber. When the number of tape travel paths exceeds a specified number,a determination is made that the recording characteristics of the servotrack have deteriorated due to deterioration resulting from using themagnetic tape numerous times, threshold reach code “0×23” is set, andthe operation is terminated.

[0135] (S48) When a specified value has been exceeded within the historyof tracking error rates of Table 32 (from most recent to 16 timestherebefore), MPU 30 determines whether or not this has occurred morethan a specified number of times. When cases in which a specified valuehas been exceeded occur more than a specified number of times, adetermination is made that magnetic tape servo track recordingcharacteristics have deteriorated, threshold reach code “0×24” is set,and the operation is terminated. By contrast, when cases in which aspecified value has been exceeded do not occur more than a specifiednumber of times, a determination is made that life has not ended,threshold reach code “0×00” is set, and the operation is terminated. Atthis time, even if the average value of the history of tracking errorrates exceeded a specified value in Step S45, when the cases in whichthe history of the tracking error rates exceeds a specified value, butthe number of times this occurred does not exceed a specified number oftimes, it is treated as no problem. The reason for this is to preventmaking a determination about life even when there is an abnormally highvalue only in a portion of the tracking error rate, and the averagevalue is raised due to this.

[0136] Threshold reach codes such as this are stored as a portion ofmedium life management information as shown in FIG. 4.

[0137] Next, the processing flow for threshold reach determinationsrelative to data read will be explained using FIG. 15.

[0138] (S50) MPU 30 determines whether or not processing in excess of aspecified number of bytes was performed during this load. Whenprocessing in excess of a specified number of bytes has not beenperformed, as explained hereinabove, to prevent making a determinationbased on data of a portion of the medium, threshold reach code “0×01” isset and the operation is terminated.

[0139] (S51) MPU 30 checks the history of the number of read processingbytes, and determines whether or not the number of times that the numberof read processing bytes exceeds a specified number of bytes is inexcess of a specified number of times. If the number of times that thenumber of read processing bytes exceeds a specified number of bytes isless than a specified number of times, similar to the explanation givenhereinabove, to prevent making a determination using data of one portionof the medium, threshold reach code “0×00” is set without carrying out acheck, and the operation is terminated.

[0140] (S52) MPU 30 determines whether or not the average value of thehistory of the read data error rates of Table 32 exceeded a specifiedvalue. When the history of read data error rates does not exceed aspecified value, a determination is made that magnetic tape readperformance has not declined, threshold reach code “0×00” is set, andthe operation is terminated.

[0141] (S53) The reporting mode determines whether or not it is theperformance-oriented mode. When it is the performance-oriented mode, adetermination is made that storage device performance has declined dueto increased retries pursuant to the deterioration of magnetic tape readcharacteristics, threshold reach code “0×32” is set, and the operationis terminated.

[0142] (S54) In the medium-oriented mode, MPU 30 determines whether ornot the number of tape travel paths of Table 32 has exceeded a specifiednumber. When the number of tape travel paths exceeds a specified number,a determination is made that read characteristics have deteriorated dueto deterioration resulting from the magnetic tape being used numeroustimes, threshold reach code “0×33” is set, and the operation isterminated.

[0143] (S55) When a specified value has been exceeded within the historyof read data error rates of Table 32 (from most recent to 16 timestherebefore), MPU 30 determines whether or not this has occurred morethan a specified number of times. When cases in which a specified valuehas been exceeded occur more than a specified number of times, adetermination is made that magnetic tape read characteristics havedeclined, threshold reach code “0×34” is set, and the operation isterminated.

[0144] When cases in which a specified value has been exceeded do notoccur more than a specified number of times, a determination is madethat magnetic tape read performance has not declined, threshold reachcode “0×00” is set, and the operation is terminated.

[0145] Thus, the write state at write (data errors, servo errors) isanalyzed, and a determination is made as to medium life. Similarly, theread state at read (data errors) is analyzed, and a determination ismade as to medium life. Further, since a plurality of items is checked,an accurate determination of medium deterioration can be made.Furthermore, since the causes of medium life deterioration are codifiedand reported, the cause of medium life deterioration can be readilyclarified.

[0146] Further, both write and read data are checked, but it is possibleto check either write data only or read data only. In this case, becausea decline in tape write characteristics causes a decline in readcharacteristics, a write-data-only check is preferable.

[0147] Furthermore, number of travel paths (distance) is utilized todetermine deterioration due to use, but life can similarly be determinedusing travel time and total number of processing bytes as well.

[0148]FIG. 16 is an example of a medium life display. Host 4 receivesanalysis results from MT drive 5 resulting from the processing of FIG.10, and a cartridge replacement request is displayed on the host 4display device as shown in FIG. 16. Volume name (cartridge name) and theMT drive number are displayed at this time. In accordance therewith, nomatter what drive or cartridge a replacement request is generated for, adetermination can be readily made even if there are a plurality ofdrives and cartridges.

[0149] Similarly, host 4 receives the above-mentioned medium lifemanagement information, and host 4 performs the analysis processing ofFIG. 14 and FIG. 15, enabling the display of a replacement request asshown in FIG. 16.

[0150] Furthermore, the replacement request and determination codesthereof can also be displayed on the MT drive 5 operator panel.

Library System

[0151] Life management such as this is even more effective in a librarysystem. FIG. 17 is a schematic of a storage system of another embodimentof the present invention, FIG. 18 is a block diagram thereof, and FIG.19 is a chart describing an example of a medium life display by thehost.

[0152] As shown in FIG. 17, a library system 6 constitutes MT drive 5, astorage shelf 7, an accessor 8, and a library controller 9. A pluralityof magnetic tape cartridges 1 is stored on storage shelf 7. For example,between 400 and 1,000 magnetic tape cartridges 1 are stored there.

[0153] The accessor (cartridge handling mechanism) 8 extracts acartridge specified by host 4 from the storage shelf 7, carries it to MTdrive 5 and loads it. Then, accessor 8 removes a cartridge for whichprocessing has been completed from MT drive 5, and returns it to storageshelf 7. Library controller 9 controls MT drive 5 and accessor 8.

[0154] By providing a plurality of MT drives 5 (there are six in thefigure), host 4 can process cartridges one after the other withoutwaiting for cartridge handling time.

[0155] This library system is used to build up a large capacitydatabase. Because cartridges are stored inside the library system, it isdifficult to know the replacement life of each cartridge. By utilizingMT drive 5 of the present invention in library system 6, the replacementlife of each cartridge can be readily detected even in an automatedsystem.

[0156] As shown in FIG. 18, MT drive 5 shown in FIG. 1 is connected tohost 4 via library controller 9. The constitution of MT drive 5, asshown in the figure, is the same as that of FIG. 1. Data from host 4 issent via SCSI I/F 35, and commands from host 4 are received by MPU 30via library controller 9.

[0157] In a library system such as this, host 4 specifies the cartridgeto be accessed to library controller 9. Library controller 9 controlsaccessor 8, and accessor 8 extracts the cartridge specified by host 4from the storage shelf 7, carries it to MT drive 5 and loads it into MTdrive 5. Then, accessor 8 removes a processed cartridge from MT drive 5,and returns it to storage shelf 7.

[0158] MT drive 5 performs read/write processing on a loaded cartridge.As described hereinabove, MT drive 5 reads out, updates and writesmedium life management information 14, and manages medium life at thistime.

[0159] As described hereinabove, MT drive 5 communicates medium lifemanagement information 14 to host 4 in response to a read buffer commandfrom host 4. In accordance therewith, it becomes possible for host 4 tomanage medium life. Further, in a system, wherein MT drive 5 analyzesmedium life management information 14, the results of analysis arereported to host 4 in response to a host 4 LOG sense command. Thus, asshown in FIG. 19, a cartridge replacement request is displayed on thedisplay device of the host 4 in accordance with the analysis results.The volume name (cartridge name), library system number, and MT drivenumber are displayed at this time. In accordance therewith, no matterwhich drive or cartridge a replacement request is generated for, adetermination can be readily made even when there are a plurality oflibrary systems.

[0160] Similarly, host 4 receives the above-mentioned medium lifemanagement information 14, and host 4 performs the analysis processingof FIG. 14 and FIG. 15, enabling the display of a replacement request asshown in FIG. 19.

[0161] In particular, when host 4 is in a location separate from librarysystem 6, it becomes possible to manage the life of a cartridge 1 oflibrary system 6 at a location separate from the operator.

[0162] Furthermore, by host 4 instructing library controller 9 toextract a cartridge for which there was a medium replacement request, itis possible for accessor 8 to eject that cartridge from library system6.

[0163] Further, the storage medium has been described as a magnetic tapecartridge, but a magnetic disk cartridge, optical disk cartridge, ormagneto-optical disk cartridge or the like can also be utilized.Furthermore, another removable, read/write-capable tape, disk, card orthe like, which does not take the shape of a cartridge, can also beutilized.

[0164] As explained hereinabove, the present invention is capable of allsorts of variations within the scope of this technical concept, andthese variations are included in the scope of the present invention.

INDUSTRIAL APPLICABILITY

[0165] The present invention is useful for managing the life of astorage medium. In particular, it makes it possible to accurately detectthe deterioration of a storage medium because it treats operatingstates, such as operating time, number of data errors, and number ofservo errors and the like at storage medium read/write, as managementinformation. Thus, the present invention can prevent the wastefulreplacement of a storage medium and the loss of data.

1. A method for managing the life of a storage medium in a storagedevice, which accesses a loaded storage medium for reading/writing datafrom/to said storage medium, comprising the steps of: reading mediumlife management information from said loaded storage medium; detectingan operating state of at least one of the reading and the writing ofdata on said storage medium, and updating said medium life managementinformation in accordance with the results of such detection; andwriting said updated medium life management information to said storagemedium upon unloading the storage medium.
 2. The method for managing thelife of a storage medium according to claim 1, further comprising thestep of reporting said medium life management information to amanagement system for managing the life of said storage medium.
 3. Themethod for managing the life of a storage medium according to claim 1,further comprising the steps of analyzing said medium life managementinformation, and of determining the life of said storage medium.
 4. Themethod for managing the life of a storage medium according to claim 1,further comprising the step of setting determination parameters for saiddetermination step.
 5. The method for managing the life of a storagemedium according to claim 3, further comprising the step of reportingsaid determination results to a managing system for managing the life ofsaid storage medium.
 6. The method for managing the life of a storagemedium according to claim 1, wherein said updating step comprises stepsof detecting a plurality of states of at least one of the reading andthe writing of data in said storage medium, and of updating said mediumlife management information according to each of said plurality ofstates.
 7. The method for managing the life of a storage mediumaccording to claim 6, further comprising the steps of analyzing each ofsaid plurality of states of medium life management information, and ofdetermining the life of said storage medium based on the results of eachanalysis.
 8. The method for managing the life of a storage mediumaccording to claim 5, wherein said determination step comprises a stepof determining the life of said storage medium based on said respectiveanalysis results, and detecting the reason for said determination. 9.The method for managing the life of a storage medium according to claim1, wherein said updating step comprises a step of detecting at least oneof an operating quantity, a data error state and a servo error state ofat least one of the reading and the writing when data is read or writtenfrom/to said storage medium, and updating said medium life managementinformation according to results of such detection.
 10. A storage devicefor accessing a loaded storage medium, and reading/writing data from/tosaid storage medium, comprising: read/write means for reading/writingdata from/to said storage medium; and control means for controlling saidread/write means, wherein said control means, develops medium lifemanagement information, which has been read from said l oaded storagemedium, to a memory, and thereafter, detects an operating state of atleast one of the reading and the writing of data in said storage mediumby said read/write means, updates said medium life managementinformation according to results of such detection, and writes saidupdated medium life management information to said storage medium uponunloading the storage medium.
 11. The storage device according to claim10, wherein said control means reports said medium life managementinformation to a managing system for managing the life of said storagemedium.
 12. The storage device according to claim 10, wherein saidcontrol means analyzes said medium life management information, anddetermines the life of said storage medium.
 13. The storage deviceaccording to claim 10, further comprising means for setting thedetermination parameters of said life.
 14. The storage device accordingto claim 12, wherein said control means reports said determinationresults to a managing system for managing the life of said storagemedium.
 15. The storage device according to claim 10, wherein saidcontrol means detects a plurality of states of at least one of thereading and the writing of data in said storage medium, and updates saidmedium life management information according to each of said pluralityof states.
 16. The storage device according to claim 15, wherein saidcontrol means analyzes each of the plurality of states of said mediumlife management information, and determines the life of said storagemedium based on the respective analysis results.
 17. The storage deviceaccording to claim 16, wherein said control means determines the life ofsaid storage medium based on said respective analysis results, anddetects the reason for said determination.
 18. The storage deviceaccording to claim 10, wherein said control means detects at least oneof an operating quantity, a data error state and a servo error state ofat least one of the reading and the writing when data is read or writtenfrom/to said storage medium, and updates said medium life managementinformation according to results of such detection.
 19. The storagedevice according to claim 10, wherein said read/write means comprisesmeans for reading/writing data from/to a magnetic tape cartridge.
 20. Astorage system comprising: a storage device for accessing a loadedstorage medium, and reading/writing data from/to said storage medium;and a managing device for managing said storage device; wherein saidstorage device reads medium life management information from said loadedstorage medium, and thereafter, detects an operating state of at leastone of the reading and the writing of data in said storage medium,updates said medium life management information according to results ofsuch detection, and writes said updated medium life managementinformation to said storage medium upon unloading the storage medium,and, in addition, reports information related to said medium lifemanagement information to said managing device in response to a requestfrom said managing device.
 21. The storage system according to claim 20,wherein said storage device analyzes said medium life managementinformation, determines the life of said storage medium, and reportssaid determination results to said managing device.
 22. The storagesystem according to claim 20, wherein said managing device analyzes saidmedium life management information reported by said storage device, anddetermines the life of said storage medium.
 23. The storage systemaccording to claim 20, wherein said storage device comprises a librarydevice, said library device comprising: a storage drive for accessing aloaded storage medium, and for reading/writing data from/to said storagemedium; and an accessor for loading a desired storage medium into saidstorage drive, and removing said storage medium from said storage drive.24. A storage medium stored a program for managing the life of a storagemedium in a storage device, which accesses a loaded storage medium forreads/writes data from/to said storage medium, wherein said program has:a program for reading medium life management information from saidloaded storage medium; a program for updating said medium lifemanagement information according to an operating state of at least oneof the reading and the writing of said storage medium data; and aprogram for writing said updated medium life management information tosaid storage medium upon unloading the storage medium.